Workers in the art of providing and using ink jet printers realize that some error conditions can be very troublesome--one such is "streaking", when one, or several, ink jet nozzles are projecting their ink streams at non-desired (non-printing) times or places, as a document moves past. In a worst case, this can results in a continuous line(s) across the subject document, at times persisting even when the document has passed beyond the print station. Other malfunctions can cause ink jets to be projected before, or after, an entire subject document passes the print station; or to be projected above the document (e.g., when check height is less than "standard")--all such resulting in ink jets projected with no document to intercept them ("bypass streaking"). In other cases a pin hole etc. may exist, or be formed, in a document, allowing an ink jet to be projected through the document ("thru-streaking").
Any, and all, such conditions can be characterized as "streaking", and are troublesome (e.g., often resulting in unacceptable print results, not to mention creating a messy pool of ink on the document transport track, in the printer, etc.)--and are obviously to be avoided or terminated (and corrected) as soon as possible. This invention is directed toward automatically detecting such "streak" conditions and providing resultant indicator signals (e.g., alarm, error-signal to stop printing action).
A typical ink jet printer system consists of 128 tiny individual jet nozzles delivering ink to inscribe a document as it passes by the print head. As mentioned, the possibility of "streak-errors" occurring in the print system calls for failure detection measures. My subject streaker detection system offers a remedy, detecting errors involving erroneous jetting of ink continuously from one or more jet nozzles (i.e., "streaking")--"streaking" being understood to also include jet-ink projected through the document material, (e.g., through a pin-hole, being leaked-through when a check is being printed.]
An object hereof is to address at least some of the foregoing problems and to provide at least some of the mentioned, and other, advantages and features.